Yes, of course, there is the two-space (US) versus one-space convention after the dot that ends a sentence. If we follow some of the conventions in the US, dot + space may signal an abbreviation rather than sentence end.
But the problem here is that Kakoune stops at dot, even at dot + nonspace, which cannot be a sentence ending and cannot be an abbreviation either (even on the US convention). This just seems wrong to me. The stopping regex should not be:
(where the space may be horizontal or vertical).
(By the way, the choice of end-of-sentence characters might be a Kakoune option worth considering; some users may want to exclude the semi-colon, for example – but this is another issue).
Actually, dot + space can also signal the end of an abbreviation (rather than sentence ending) in French, Spanish, Portuguese, etc. So stopping at dot + space will sometimes catch abbreviations rather than sentence endings, but this is better than stopping any dot, which catches a) sentence endings, b) abbreviations, c) the initial dot of
... [what we should catch is the last of the 3 dots, the one before the space], and d) any word with dots inside, such as email adresses and many standard functions in the R statistical language, etc.